DONALD MACDONALD
1516 Folsom St.
San Francisco, CA
94104, USA
Donald MacDonald Architects LLC
DONALD MACDONALD
1516 Folsom St.
San Francisco, CA
94104, USA
California
This bridge study builds upon the success of the rolling bascule bridge typology, elevating this simple form into a distinctive and imaginative icon.
Forming one-third of a circle, the masted counterweights are outlined for dramatic effect in red. The circle, when opened, is split into two and rests on the deck, awaiting the repose of the closed position. The circle forms a unique frame for the urban context and river basin beyond.
The steel trapezoidal box bascule structure allows for prefabrication off-site and ease of maintenance and inspection. To emphasize the dynamic kinetic display, large-toothed gears of the bascule track and hydraulic pistons are readily visible when the bridge is lifted.
A cantilevered pedestrian walkway thins the bridge edge, buffered from the roadway by the bascule superstructure. A delicate guardrail of interlocking rings plays upon the larger circular form of the bascule and draws inspiration from the rippled reflections in the water.
A pair of sculpted concrete bascule basins are corbeled in the reflection of the bridge’s resting circular bascule form and support the steel rolling bascule spans. The approach span piers echo these corbels as the bridge meets the landscape.
DONALD MACDONALD
1516 Folsom St.
San Francisco, CA
94104, USA